drw.c

   1 /* See LICENSE file for copyright and license details. */
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <X11/Xlib.h>
   6 #include <X11/Xft/Xft.h>
   7
   8 #include "drw.h"
   9 #include "util.h"
  10
  11 #define UTF_INVALID 0xFFFD
  12 #define UTF_SIZ     4
  13
  14 static const unsigned char utfbyte[UTF_SIZ + 1] = {0x80,    0, 0xC0, 0xE0, 0xF0};
  15 static const unsigned char utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
  16 static const long utfmin[UTF_SIZ + 1] = {       0,    0,  0x80,  0x800,  0x10000};
  17 static const long utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
  18
  19 static long
  20 utf8decodebyte(const char c, size_t *i)
  21 {
  22         for (*i = 0; *i < (UTF_SIZ + 1); ++(*i))
  23                 if (((unsigned char)c & utfmask[*i]) == utfbyte[*i])
  24                         return (unsigned char)c & ~utfmask[*i];
  25         return 0;
  26 }
  27
  28 static size_t
  29 utf8validate(long *u, size_t i)
  30 {
  31         if (!BETWEEN(*u, utfmin[i], utfmax[i]) || BETWEEN(*u, 0xD800, 0xDFFF))
  32                 *u = UTF_INVALID;
  33         for (i = 1; *u > utfmax[i]; ++i)
  34                 ;
  35         return i;
  36 }
  37
  38 static size_t
  39 utf8decode(const char *c, long *u, size_t clen)
  40 {
  41         size_t i, j, len, type;
  42         long udecoded;
  43
  44         *u = UTF_INVALID;
  45         if (!clen)
  46                 return 0;
  47         udecoded = utf8decodebyte(c[0], &len);
  48         if (!BETWEEN(len, 1, UTF_SIZ))
  49                 return 1;
  50         for (i = 1, j = 1; i < clen && j < len; ++i, ++j) {
  51                 udecoded = (udecoded << 6) | utf8decodebyte(c[i], &type);
  52                 if (type)
  53                         return j;
  54         }
  55         if (j < len)
  56                 return 0;
  57         *u = udecoded;
  58         utf8validate(u, len);
  59
  60         return len;
  61 }
  62
  63 Drw *
  64 drw_create(Display *dpy, int screen, Window root, unsigned int w, unsigned int h)
  65 {
  66         Drw *drw = ecalloc(1, sizeof(Drw));
  67
  68         drw->dpy = dpy;
  69         drw->screen = screen;
  70         drw->root = root;
  71         drw->w = w;
  72         drw->h = h;
  73         drw->drawable = XCreatePixmap(dpy, root, w, h, DefaultDepth(dpy, screen));
  74         drw->gc = XCreateGC(dpy, root, 0, NULL);
  75         XSetLineAttributes(dpy, drw->gc, 1, LineSolid, CapButt, JoinMiter);
  76
  77         return drw;
  78 }
  79
  80 void
  81 drw_resize(Drw *drw, unsigned int w, unsigned int h)
  82 {
  83         if (!drw)
  84                 return;
  85
  86         drw->w = w;
  87         drw->h = h;
  88         if (drw->drawable)
  89                 XFreePixmap(drw->dpy, drw->drawable);
  90         drw->drawable = XCreatePixmap(drw->dpy, drw->root, w, h, DefaultDepth(drw->dpy, drw->screen));
  91 }
  92
  93 void
  94 drw_free(Drw *drw)
  95 {
  96         XFreePixmap(drw->dpy, drw->drawable);
  97         XFreeGC(drw->dpy, drw->gc);
  98         free(drw);
  99 }
 100
 101 /* This function is an implementation detail. Library users should use
 102  * drw_fontset_create instead.
 103  */
 104 static Fnt *
 105 xfont_create(Drw *drw, const char *fontname, FcPattern *fontpattern)
 106 {
 107         Fnt *font;
 108         XftFont *xfont = NULL;
 109         FcPattern *pattern = NULL;
 110
 111         if (fontname) {
 112                 /* Using the pattern found at font->xfont->pattern does not yield the
 113                  * same substitution results as using the pattern returned by
 114                  * FcNameParse; using the latter results in the desired fallback
 115                  * behaviour whereas the former just results in missing-character
 116                  * rectangles being drawn, at least with some fonts. */
 117                 if (!(xfont = XftFontOpenName(drw->dpy, drw->screen, fontname))) {
 118                         fprintf(stderr, "error, cannot load font from name: '%s'\n", fontname);
 119                         return NULL;
 120                 }
 121                 if (!(pattern = FcNameParse((FcChar8 *) fontname))) {
 122                         fprintf(stderr, "error, cannot parse font name to pattern: '%s'\n", fontname);
 123                         XftFontClose(drw->dpy, xfont);
 124                         return NULL;
 125                 }
 126         } else if (fontpattern) {
 127                 if (!(xfont = XftFontOpenPattern(drw->dpy, fontpattern))) {
 128                         fprintf(stderr, "error, cannot load font from pattern.\n");
 129                         return NULL;
 130                 }
 131         } else {
 132                 die("no font specified.");
 133         }
 134
 135         /* Do not allow using color fonts. This is a workaround for a BadLength
 136          * error from Xft with color glyphs. Modelled on the Xterm workaround. See
 137          * https://bugzilla.redhat.com/show_bug.cgi?id=1498269
 138          * https://lists.suckless.org/dev/1701/30932.html
 139          * https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=916349
 140          * and lots more all over the internet.
 141          */
 142         FcBool iscol;
 143         if(FcPatternGetBool(xfont->pattern, FC_COLOR, 0, &iscol) == FcResultMatch && iscol) {
 144                 XftFontClose(drw->dpy, xfont);
 145                 return NULL;
 146         }
 147
 148         font = ecalloc(1, sizeof(Fnt));
 149         font->xfont = xfont;
 150         font->pattern = pattern;
 151         font->h = xfont->ascent + xfont->descent;
 152         font->dpy = drw->dpy;
 153
 154         return font;
 155 }
 156
 157 static void
 158 xfont_free(Fnt *font)
 159 {
 160         if (!font)
 161                 return;
 162         if (font->pattern)
 163                 FcPatternDestroy(font->pattern);
 164         XftFontClose(font->dpy, font->xfont);
 165         free(font);
 166 }
 167
 168 Fnt*
 169 drw_fontset_create(Drw* drw, const char *fonts[], size_t fontcount)
 170 {
 171         Fnt *cur, *ret = NULL;
 172         size_t i;
 173
 174         if (!drw || !fonts)
 175                 return NULL;
 176
 177         for (i = 1; i <= fontcount; i++) {
 178                 if ((cur = xfont_create(drw, fonts[fontcount - i], NULL))) {
 179                         cur->next = ret;
 180                         ret = cur;
 181                 }
 182         }
 183         return (drw->fonts = ret);
 184 }
 185
 186 void
 187 drw_fontset_free(Fnt *font)
 188 {
 189         if (font) {
 190                 drw_fontset_free(font->next);
 191                 xfont_free(font);
 192         }
 193 }
 194
 195 void
 196 drw_clr_create(Drw *drw, Clr *dest, const char *clrname)
 197 {
 198         if (!drw || !dest || !clrname)
 199                 return;
 200
 201         if (!XftColorAllocName(drw->dpy, DefaultVisual(drw->dpy, drw->screen),
 202                                DefaultColormap(drw->dpy, drw->screen),
 203                                clrname, dest))
 204                 die("error, cannot allocate color '%s'", clrname);
 205 }
 206
 207 /* Wrapper to create color schemes. The caller has to call free(3) on the
 208  * returned color scheme when done using it. */
 209 Clr *
 210 drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount)
 211 {
 212         size_t i;
 213         Clr *ret;
 214
 215         /* need at least two colors for a scheme */
 216         if (!drw || !clrnames || clrcount < 2 || !(ret = ecalloc(clrcount, sizeof(XftColor))))
 217                 return NULL;
 218
 219         for (i = 0; i < clrcount; i++)
 220                 drw_clr_create(drw, &ret[i], clrnames[i]);
 221         return ret;
 222 }
 223
 224 void
 225 drw_setfontset(Drw *drw, Fnt *set)
 226 {
 227         if (drw)
 228                 drw->fonts = set;
 229 }
 230
 231 void
 232 drw_setscheme(Drw *drw, Clr *scm)
 233 {
 234         if (drw)
 235                 drw->scheme = scm;
 236 }
 237
 238 void
 239 drw_rect(Drw *drw, int x, int y, unsigned int w, unsigned int h, int filled, int invert)
 240 {
 241         if (!drw || !drw->scheme)
 242                 return;
 243         XSetForeground(drw->dpy, drw->gc, invert ? drw->scheme[ColBg].pixel : drw->scheme[ColFg].pixel);
 244         if (filled)
 245                 XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
 246         else
 247                 XDrawRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w - 1, h - 1);
 248 }
 249
 250 int
 251 drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad, const char *text, int invert)
 252 {
 253         char buf[1024];
 254         int ty;
 255         unsigned int ew;
 256         XftDraw *d = NULL;
 257         Fnt *usedfont, *curfont, *nextfont;
 258         size_t i, len;
 259         int utf8strlen, utf8charlen, render = x || y || w || h;
 260         long utf8codepoint = 0;
 261         const char *utf8str;
 262         FcCharSet *fccharset;
 263         FcPattern *fcpattern;
 264         FcPattern *match;
 265         XftResult result;
 266         int charexists = 0;
 267
 268         if (!drw || (render && !drw->scheme) || !text || !drw->fonts)
 269                 return 0;
 270
 271         if (!render) {
 272                 w = ~w;
 273         } else {
 274                 XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColFg : ColBg].pixel);
 275                 XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
 276                 d = XftDrawCreate(drw->dpy, drw->drawable,
 277                                   DefaultVisual(drw->dpy, drw->screen),
 278                                   DefaultColormap(drw->dpy, drw->screen));
 279                 x += lpad;
 280                 w -= lpad;
 281         }
 282
 283         usedfont = drw->fonts;
 284         while (1) {
 285                 utf8strlen = 0;
 286                 utf8str = text;
 287                 nextfont = NULL;
 288                 while (*text) {
 289                         utf8charlen = utf8decode(text, &utf8codepoint, UTF_SIZ);
 290                         for (curfont = drw->fonts; curfont; curfont = curfont->next) {
 291                                 charexists = charexists || XftCharExists(drw->dpy, curfont->xfont, utf8codepoint);
 292                                 if (charexists) {
 293                                         if (curfont == usedfont) {
 294                                                 utf8strlen += utf8charlen;
 295                                                 text += utf8charlen;
 296                                         } else {
 297                                                 nextfont = curfont;
 298                                         }
 299                                         break;
 300                                 }
 301                         }
 302
 303                         if (!charexists || nextfont)
 304                                 break;
 305                         else
 306                                 charexists = 0;
 307                 }
 308
 309                 if (utf8strlen) {
 310                         drw_font_getexts(usedfont, utf8str, utf8strlen, &ew, NULL);
 311                         /* shorten text if necessary */
 312                         for (len = MIN(utf8strlen, sizeof(buf) - 1); len && ew > w; len--)
 313                                 drw_font_getexts(usedfont, utf8str, len, &ew, NULL);
 314
 315                         if (len) {
 316                                 memcpy(buf, utf8str, len);
 317                                 buf[len] = '\0';
 318                                 if (len < utf8strlen)
 319                                         for (i = len; i && i > len - 3; buf[--i] = '.')
 320                                                 ; /* NOP */
 321
 322                                 if (render) {
 323                                         ty = y + (h - usedfont->h) / 2 + usedfont->xfont->ascent;
 324                                         XftDrawStringUtf8(d, &drw->scheme[invert ? ColBg : ColFg],
 325                                                           usedfont->xfont, x, ty, (XftChar8 *)buf, len);
 326                                 }
 327                                 x += ew;
 328                                 w -= ew;
 329                         }
 330                 }
 331
 332                 if (!*text) {
 333                         break;
 334                 } else if (nextfont) {
 335                         charexists = 0;
 336                         usedfont = nextfont;
 337                 } else {
 338                         /* Regardless of whether or not a fallback font is found, the
 339                          * character must be drawn. */
 340                         charexists = 1;
 341
 342                         fccharset = FcCharSetCreate();
 343                         FcCharSetAddChar(fccharset, utf8codepoint);
 344
 345                         if (!drw->fonts->pattern) {
 346                                 /* Refer to the comment in xfont_create for more information. */
 347                                 die("the first font in the cache must be loaded from a font string.");
 348                         }
 349
 350                         fcpattern = FcPatternDuplicate(drw->fonts->pattern);
 351                         FcPatternAddCharSet(fcpattern, FC_CHARSET, fccharset);
 352                         FcPatternAddBool(fcpattern, FC_SCALABLE, FcTrue);
 353                         FcPatternAddBool(fcpattern, FC_COLOR, FcFalse);
 354
 355                         FcConfigSubstitute(NULL, fcpattern, FcMatchPattern);
 356                         FcDefaultSubstitute(fcpattern);
 357                         match = XftFontMatch(drw->dpy, drw->screen, fcpattern, &result);
 358
 359                         FcCharSetDestroy(fccharset);
 360                         FcPatternDestroy(fcpattern);
 361
 362                         if (match) {
 363                                 usedfont = xfont_create(drw, NULL, match);
 364                                 if (usedfont && XftCharExists(drw->dpy, usedfont->xfont, utf8codepoint)) {
 365                                         for (curfont = drw->fonts; curfont->next; curfont = curfont->next)
 366                                                 ; /* NOP */
 367                                         curfont->next = usedfont;
 368                                 } else {
 369                                         xfont_free(usedfont);
 370                                         usedfont = drw->fonts;
 371                                 }
 372                         }
 373                 }
 374         }
 375         if (d)
 376                 XftDrawDestroy(d);
 377
 378         return x + (render ? w : 0);
 379 }
 380
 381 void
 382 drw_map(Drw *drw, Window win, int x, int y, unsigned int w, unsigned int h)
 383 {
 384         if (!drw)
 385                 return;
 386
 387         XCopyArea(drw->dpy, drw->drawable, win, drw->gc, x, y, w, h, x, y);
 388         XSync(drw->dpy, False);
 389 }
 390
 391 unsigned int
 392 drw_fontset_getwidth(Drw *drw, const char *text)
 393 {
 394         if (!drw || !drw->fonts || !text)
 395                 return 0;
 396         return drw_text(drw, 0, 0, 0, 0, 0, text, 0);
 397 }
 398
 399 void
 400 drw_font_getexts(Fnt *font, const char *text, unsigned int len, unsigned int *w, unsigned int *h)
 401 {
 402         XGlyphInfo ext;
 403
 404         if (!font || !text)
 405                 return;
 406
 407         XftTextExtentsUtf8(font->dpy, font->xfont, (XftChar8 *)text, len, &ext);
 408         if (w)
 409                 *w = ext.xOff;
 410         if (h)
 411                 *h = font->h;
 412 }
 413
 414 Cur *
 415 drw_cur_create(Drw *drw, int shape)
 416 {
 417         Cur *cur;
 418
 419         if (!drw || !(cur = ecalloc(1, sizeof(Cur))))
 420                 return NULL;
 421
 422         cur->cursor = XCreateFontCursor(drw->dpy, shape);
 423
 424         return cur;
 425 }
 426
 427 void
 428 drw_cur_free(Drw *drw, Cur *cursor)
 429 {
 430         if (!cursor)
 431                 return;
 432
 433         XFreeCursor(drw->dpy, cursor->cursor);
 434         free(cursor);
 435 }